Radar Synthesizer Architecture for Coherent Doppler Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current radar systems are expensive and complex, making them costly for applications like weather and marine radar, and they often require multiple oscillators which can lead to coherence issues and difficulty in measuring the Doppler effect.
Innovation Solution
A radar system utilizing direct digital synthesizer (DDS) circuitry and phase-locked loop (PLL) circuitry to generate sinusoidal signals, with a single clock source for both transmitter and receiver, and frequency multiplier circuitry to operate in S-band and X-band frequencies, reducing component count and cost while maintaining performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional radar systems use multiple oscillators to generate signals, then they can achieve signal generation capability, but they suffer from coherence issues and difficulty in measuring the Doppler effect
Solution Approach 1:
The patent merges the functions of multiple oscillators into a single oscillator that serves both the transmitter and receiver. This single oscillator generates a clock signal that is distributed to both chains, ensuring coherence and eliminating the problems associated with multiple independent oscillators while reducing device complexity
Solution Approach 2:
The single oscillator in the patent performs multiple functions by generating the clock signal for both the transmitter chain and receiver chain. This multi-functional approach replaces what would traditionally require separate oscillators, improving coherence while reducing the number of components
2Measurement precision
If radar systems use higher frequency bands (X-band) for operation, then they achieve better resolution and performance, but the system complexity and cost increase significantly
Solution Approach 1:
The patent achieves frequency band flexibility through parameter changes in the DDS circuitry. By programmatically adjusting the frequency parameters of the direct digital synthesizer, the system can operate in both S-band and X-band frequencies using the same hardware architecture, avoiding the need for different hardware designs for different bands
3Measurement precision
If radar systems use more semiconductor parts to achieve better performance, then they improve measurement precision and reliability, but the cost and device complexity increase
Solution Approach 1:
The patent combines the signal generation functions for both transmitter and receiver into a single oscillator and DDS system. This merging reduces the total number of semiconductor parts while maintaining the ability to perform accurate Doppler measurements through the coherent signal generation and processing
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system achieves high-performance radar functionality at lower costs by using fewer and lower-cost components, improving coherence and enabling accurate velocity measurement through the Doppler effect, while allowing operation in multiple frequency bands.
Implementation Method 1
The DDS circuitry may be configured to deliver the DDS signal to drive phase-locked loop (PLL) circuitry of the synthesizer to generate a sinusoidal signal
Implementation Method 2
The frequency of the return signal is based on the velocity of the object because of the Doppler effect. The radar system may determine the change in frequency due to the Doppler effect by comparing the frequency of the return signal to the frequency of the radar signal
Implementation Method 3
frequency multiplier circuitry to operate in S-band and X-band frequencies
Data Source
AI summary
In some examples, a radar system includes first direct digital synthesizer (DDS) circuitry and first phase-locked loop (PLL) circuitry configured to generate a first sinusoidal signal based on a first DDS signal generated by the first DDS circuitry. In some examples, the radar system further includes transmitter circuitry configured to generate a radar signal based on the first sinusoidal signal. In some examples, the radar system also includes one or more antennas configured to transmit the radar signal and receive a return signal based on the radar signal. In some examples, the radar system includes second DDS circuitry, second PLL circuitry configured to generate a second sinusoidal signal based on a second DDS signal generated by the second DDS circuitry, and receiver circuitry configured to process the return signal based on the second sinusoidal signal.